[PATCH 0/2] gcc: backport patch to fix miscompilation problem on mips64

[PATCH 0/2] gcc: backport patch to fix miscompilation problem on mips64

[Chen Qi]

The following changes since commit 2e1eb9ab12802d52465e6ae636c3f6a40ffb098c:

  bitbake: tests/fetch: Add ftp test url (2017-11-07 15:02:19 +0000)

are available in the git repository at:

  git://git.pokylinux.org/poky-contrib ChenQi/bug12266
  http://git.pokylinux.org/cgit.cgi/poky-contrib/log/?h=ChenQi/bug12266

Chen Qi (2):
  systemd: remove useless options for mips64
  gcc: backport patch to fix miscompilation on mips64

 meta/recipes-core/systemd/systemd_234.bb           |  3 --
 meta/recipes-devtools/gcc/gcc-7.2.inc              |  1 +
 .../gcc-7.2/0001-PR-rtl-optimization-81803.patch   | 52 ++++++++++++++++++++++
 3 files changed, 53 insertions(+), 3 deletions(-)
 create mode 100644 meta/recipes-devtools/gcc/gcc-7.2/0001-PR-rtl-optimization-81803.patch

-- 
1.9.1

[PATCH 1/2] systemd: remove useless options for mips64

[Chen Qi]

Looking back the history, we had problem with systemd on qemumips64
which is also related to compilation flags. We solved that by using
tweaking FULL_OPTIMIZATION for mips64 to have "-fno-tree-switch-conversion
-fno-tree-tail-merge".

Now systemd has been upgraded to 234, and we don't have the above problem
any more, thus removing these flags.

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
---
 meta/recipes-core/systemd/systemd_234.bb | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/meta/recipes-core/systemd/systemd_234.bb b/meta/recipes-core/systemd/systemd_234.bb
index 36fd3f8..971226f 100644
--- a/meta/recipes-core/systemd/systemd_234.bb
+++ b/meta/recipes-core/systemd/systemd_234.bb
@@ -158,9 +158,6 @@ CFLAGS .= "${@bb.utils.contains('PACKAGECONFIG', 'valgrind', ' -DVALGRIND=1', ''
 # disable problematic GCC 5.2 optimizations [YOCTO #8291]
 FULL_OPTIMIZATION_append_arm = " -fno-schedule-insns -fno-schedule-insns2"
 
-# Avoid login failure on qemumips64 when pam is enabled
-FULL_OPTIMIZATION_append_mips64 = " -fno-tree-switch-conversion -fno-tree-tail-merge"
-
 COMPILER_NM ?= "${HOST_PREFIX}gcc-nm"
 COMPILER_AR ?= "${HOST_PREFIX}gcc-ar"
 COMPILER_RANLIB ?= "${HOST_PREFIX}gcc-ranlib"
-- 
1.9.1

[PATCH 2/2] gcc: backport patch to fix miscompilation on mips64

[Chen Qi]

Backport a patch to fix miscompilation on mips64.

We've observed strange behaviour of `systemctl status <xxx> on qemumips64.
The output of the command is like `systemctl show <xxx>', which is incorrect.

The problem is due to the miscompilation of gcc for mips64 platform, thus
backporting patch from upstream to fix this problem.

[YOCTO #12266]

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
---
 meta/recipes-devtools/gcc/gcc-7.2.inc              |  1 +
 .../gcc-7.2/0001-PR-rtl-optimization-81803.patch   | 52 ++++++++++++++++++++++
 2 files changed, 53 insertions(+)
 create mode 100644 meta/recipes-devtools/gcc/gcc-7.2/0001-PR-rtl-optimization-81803.patch

diff --git a/meta/recipes-devtools/gcc/gcc-7.2.inc b/meta/recipes-devtools/gcc/gcc-7.2.inc
index 5883bc6..ebed5b9 100644
--- a/meta/recipes-devtools/gcc/gcc-7.2.inc
+++ b/meta/recipes-devtools/gcc/gcc-7.2.inc
@@ -78,6 +78,7 @@ SRC_URI = "\
            ${BACKPORTS} \
 "
 BACKPORTS = "\
+           file://0001-PR-rtl-optimization-81803.patch \
 "
 SRC_URI[md5sum] = "ff370482573133a7fcdd96cd2f552292"
 SRC_URI[sha256sum] = "1cf7adf8ff4b5aa49041c8734bbcf1ad18cc4c94d0029aae0f4e48841088479a"
diff --git a/meta/recipes-devtools/gcc/gcc-7.2/0001-PR-rtl-optimization-81803.patch b/meta/recipes-devtools/gcc/gcc-7.2/0001-PR-rtl-optimization-81803.patch
new file mode 100644
index 0000000..292e734
--- /dev/null
+++ b/meta/recipes-devtools/gcc/gcc-7.2/0001-PR-rtl-optimization-81803.patch
@@ -0,0 +1,52 @@
+From 5cbb8e6b1122092b3eaabd4270b2f316aa40407c Mon Sep 17 00:00:00 2001
+From: ebotcazou <ebotcazou@138bc75d-0d04-0410-961f-82ee72b054a4>
+Date: Tue, 31 Oct 2017 18:27:52 +0000
+Subject: [PATCH] 	PR rtl-optimization/81803 	* lra-constraints.c
+ (curr_insn_transform): Also reload the whole 	register for a strict subreg
+ no wider than a word if this is for 	a WORD_REGISTER_OPERATIONS target.
+
+git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@254275 138bc75d-0d04-0410-961f-82ee72b054a4
+
+Upstream-Status: Backport
+
+This patch removes changes to Changelog from the original patch upstream. This is
+because we are backporting a patch to a stable version, making changes to Changelog,
+especially up '* GCC 7.2.0 released.', feels a little weird.
+
+Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
+---
+ gcc/lra-constraints.c | 11 ++++++++---
+ 2 files changed, 16 insertions(+), 3 deletions(-)
+
+diff --git a/gcc/lra-constraints.c b/gcc/lra-constraints.c
+index a423f069836..3758409bb9c 100644
+--- a/gcc/lra-constraints.c
++++ b/gcc/lra-constraints.c
+@@ -4207,8 +4207,9 @@ curr_insn_transform (bool check_only_p)
+ 	      reg = SUBREG_REG (*loc);
+ 	      byte = SUBREG_BYTE (*loc);
+ 	      if (REG_P (reg)
+-		  /* Strict_low_part requires reload the register not
+-		     the sub-register.	*/
++		  /* Strict_low_part requires reloading the register and not
++		     just the subreg.  Likewise for a strict subreg no wider
++		     than a word for WORD_REGISTER_OPERATIONS targets.  */
+ 		  && (curr_static_id->operand[i].strict_low
+ 		      || (!paradoxical_subreg_p (mode, GET_MODE (reg))
+ 			  && (hard_regno
+@@ -4219,7 +4220,11 @@ curr_insn_transform (bool check_only_p)
+ 			  && (goal_alt[i] == NO_REGS
+ 			      || (simplify_subreg_regno
+ 				  (ira_class_hard_regs[goal_alt[i]][0],
+-				   GET_MODE (reg), byte, mode) >= 0)))))
++				   GET_MODE (reg), byte, mode) >= 0)))
++		      || (GET_MODE_PRECISION (mode)
++			  < GET_MODE_PRECISION (GET_MODE (reg))
++			  && GET_MODE_SIZE (GET_MODE (reg)) <= UNITS_PER_WORD
++			  && WORD_REGISTER_OPERATIONS)))
+ 		{
+ 		  /* An OP_INOUT is required when reloading a subreg of a
+ 		     mode wider than a word to ensure that data beyond the
+-- 
+2.13.0
+
-- 
1.9.1